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Last reviewed: 24 Jul 2025 Last updated: 15 Nov 2024 Summary Hypoparathyroidism has a wide variety of presentations: from the asymptomatic patient with dramatically low serum calcium to the acutely symptomatic patient with neuromuscular irritability, tetany, painful muscle cramps, stridor, and even seizures with low serum calcium in the emergency department or recovery room. Majority of cases are post-surgery for benign and malignant thyroid disorders, hyperparathyroidism, and laryngeal or other head and neck cancers. Nonsurgical etiologies include: rare genetic conditions and syndromes; autoimmune destruction of the glands; destruction or invasion due to tumor, radiation, or infiltration by iron or copper; hypomagnesemia and magnesium depletion; and idiopathic. Laboratory testing should confirm low ionized or albumin-corrected total calcium and low or inappropriately normal intact plasma parathyroid hormone, while also verifying normal serum magnesium and 25-hydroxyvitamin D levels. If symptoms are present, replacement of calcium and/or magnesium should be promptly instituted with careful monitoring along with activated vitamin D metabolites for chronic treatment. DefinitionHypoparathyroidism is caused by relative or absolute deficiency of plasma parathyroid hormone (PTH) synthesis and secretion. This leads to low albumin-corrected serum total calcium and elevated serum phosphate. Signs and symptoms can involve the neuromuscular, psychiatric, cardiac, ocular, dermatologic, gastrointestinal, and renal/urologic systems. Patients can also be asymptomatic. Definitions of permanent postsurgical hypoparathyroidism vary. Persistently low intact PTH levels in the presence of hypocalcemia requiring treatment for at least 6 months (some guidelines state at least 12 months) post-procedure generally indicates that the condition is permanent. History and examKey diagnostic factors history of thyroid, parathyroid, or laryngeal surgery chronic alcoholism malnutrition, malabsorption, diarrhea muscle twitches, spasms, cramps paresthesias, numbness, tingling poor memory, slowed thinking Chvostek sign convulsions irregular heart beat, tachycardia Trousseau sign Full details Other diagnostic factors anxiety dry hair, brittle nails cataracts history of mucocutaneous candidiasis history of chronic transfusions in patients with thalassemia dyspnea laryngeal spasm Full details Risk factors thyroid surgery parathyroid surgery hypomagnesemia moderate and chronic maternal hypercalcemia (neonatal hypocalcemia) autosomal dominant conditions (e.g., mutations in CASR, GATA3) hereditary hemochromatosis transfusional iron overload in thalassemia Wilson disease metastatic cancer Full details
1st tests to order serum calcium plasma intact PTH serum albumin serum magnesium serum 25-hydroxyvitamin D serum phosphorus serum creatinine ECG Full details Tests to consider 24-hour urine calcium, creatinine 24-hour magnesium, creatinine liver function tests arterial blood gases (ABGs) serum free thyroxine, thyrotropin morning cortisol and adrenocorticotropin (ACTH) stimulation testing complete blood count serum iron, transferrin, ferritin serum copper ophthalmologic exam audiology renal imaging autoantibodies to type 1 interferon or 21-hydroxylase gene sequencing Full details
INITIAL severe symptomatic hypocalcemia (albumin-corrected serum total calcium <7.5 mg/dL [<1.88 mmol/L]) ACUTE asymptomatic temporary postoperative hypocalcemia ONGOING chronic hypoparathyroidism
ContributorsVIEW ALLAuthors Authors Dolores Shoback, MD Professor of Medicine University of California San Francisco Endocrine Research Unit San Francisco VA Medical Center San Francisco CA DisclosuresDS declares that her institution receives research money from Ascendis Pharmaceuticals to conduct a clinical trial in hypoparathyroid patients on which she is the Principal Investigator. This company is testing a new treatment for hypoparathyroidism. DS has participated in an advisory board for Ascendis (Dec 2022) to review data on this new treatment. Quan-Yang Duh, MD, FACS Professor of Surgery Section of Endocrine Surgery University of California San Francisco San Francisco CA DisclosuresQYD declares that he has no competing interests. Acknowledgements Professors Dolores Shoback and Quan-Yang Duh would like to gratefully acknowledge Professor Ronald Merrell, a previous contributor to this topic. DisclosuresRM declares that he has no competing interests. VIEW ALLPeer reviewers Peer reviewers Wail Malaty, MD Adjunct Clinical Professor Department of Family Medicine University of North Carolina Chapel Hill NC DisclosuresWM declares that he has no competing interests. References Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible. Key articlesKhan AA, Bilezikian JP, Brandi ML, et al. Evaluation and management of hypoparathyroidism summary statement and guidelines from the Second International Workshop. J Bone Miner Res. 2022 Dec;37(12):2568-85.Full text Abstract Mannstadt M, Cianferotti L, Gafni RI, et al. Hypoparathyroidism: genetics and diagnosis. J Bone Miner Res. 2022 Dec;37(12):2615-29.Full text Abstract Orloff LA, Wiseman SM, Bernet VJ, et al. American Thyroid Association statement on postoperative hypoparathyroidism: diagnosis, prevention, and management in adults. Thyroid. 2018 Jul;28(7):830-41.Full text Abstract Gafni RI, Collins MT. Hypoparathyroidism. N Engl J Med. 2019 May 2;380(18):1738-47. Abstract Reference articlesA full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice. (责任编辑：) |
